A carbon sink calculation method for metal mine restoration areas

Abstract

The present invention discloses a carbon sink calculation method for a metal mine restoration area, which belongs to the field of carbon sink detection technology. The method comprises the following steps: dividing the metal mine restoration area into a plurality of different ecological region quadrats, calculating the sum of carbon reserves in different ecological regions, and recording it as C. E ; Soil samples were collected to assess the impact of soil erosion on carbon storage in the metal mine restoration area. By measuring the amount of soil erosion and the organic carbon content of the surface soil, the carbon loss caused by soil erosion was calculated, which was recorded as C SE Assess the impact of acid mine drainage treatment on carbon emissions in the remediation area. By obtaining the runoff conditions and relevant carbon emission factors in the remediation area, calculate the carbon emissions (GHG) generated by acid mine drainage treatment. E ; Set the measurement period and calculate the total carbon sink ΔC in the metal mine restoration area during the measurement period according to the formula T The carbon sink calculation method of the present invention can provide a comprehensive and quantitative assessment of the total carbon sink capacity of a mine restoration area.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon sink detection, and in particular to a carbon sink calculation method for a metal mine restoration area. Background Art

[0002] Against the backdrop of global climate change, the assessment of the carbon cycle and carbon sinks has become increasingly important. The carbon cycle refers to the natural circulation of carbon among Earth's major spheres: the atmosphere, biosphere, geology, and oceans. Carbon sinks, defined as the ability to absorb and store atmospheric carbon dioxide for extended periods, play a key role in mitigating rising greenhouse gas concentrations and climate change. Ecosystems, particularly forests, wetlands, and oceans, serve as major natural carbon sinks and play a vital role in maintaining global carbon balance.

[0003] Ecological restoration of abandoned metal mining sites is not only crucial for ecological security and environmental beautification, but also a crucial way to enhance regional carbon sequestration capacity. Mining activities are often associated with significant carbon emissions and ecosystem damage. Ecological restoration of abandoned sites can effectively restore soil fertility, promote vegetation recovery, and thus enhance carbon sequestration capacity, positively impacting the carbon cycle.

[0004] In view of this, this application is filed. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a carbon sink calculation method for metal mine restoration areas. The carbon sink calculation method of the present invention comprehensively considers the increase in carbon reserves, carbon loss caused by soil erosion, and carbon emissions during wastewater treatment. It not only accurately calculates the carbon reserves in the mine restoration area, but also provides a comprehensive and quantitative assessment of the carbon sink capacity of the mine restoration area, which helps to more accurately understand the impact of restoration activities on the carbon cycle.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A method for calculating carbon sequestration in a metal mine restoration area comprises the following steps:

[0008] (1) Based on the vegetation characteristics of the metal mine restoration area, the metal mine restoration area was divided into several different ecological region quadrats, and the sum of carbon storage in different ecological regions was calculated, which was recorded as C E ;

[0009] (2) Collect soil samples to evaluate the impact of soil erosion on carbon storage in the metal mine restoration area. By measuring the amount of soil erosion and the organic carbon content of the surface soil, calculate the amount of carbon loss caused by soil erosion, which is recorded as C SE ;

[0010] (3) Evaluate the impact of acid mine drainage treatment on carbon emissions in the remediation area. By obtaining the runoff conditions and relevant carbon emission factors in the remediation area, calculate the carbon emissions (GHG) generated by acid mine drainage treatment. E ;

[0011] (4) Set a measurement period and repeat steps (1) to (3) according to the measurement period, and compare the carbon storage C of the metal mine restoration area at the beginning and end of each measurement period. E,1 and C E,2 , carbon loss C SE,1 and C SE,2 , carbon emissions GHG E,1 and GHG E,2 , calculate the ecological carbon sink ΔC E , Carbon loss change ΔC SE and the change in carbon emissions ΔGHG E , calculate the total carbon sink ΔC in the metal mine restoration area during the measurement period according to the formula T , ΔC T =ΔC E -ΔC SE -ΔGHG E .

[0012] As a preferred embodiment of the present invention, the ecological region sample plot includes at least one of a herbaceous region and a woody region.

[0013] As a preferred embodiment of the present invention, the sample area of ​​the herbaceous area is 0.16~4m 2 The sample area of ​​the woody area is 25~400m 2 The number of sample plots in the herbaceous area and woody area is ≥3.

[0014] As a preferred embodiment of the present invention, the C E =C Above +C Below +C Litter +C SOC ;

[0015] Among them, the C Above is the carbon storage of aboveground organisms in the metal mine restoration area, where C Below is the carbon storage of underground organisms in the metal mine restoration area, the C Litter is the carbon storage of litter in the metal mine restoration area, the C SOC It is the soil organic carbon storage in the metal mine restoration area.

[0016] As a preferred embodiment of the present invention, the C Above =C H-A +C T-A, wherein the C H-A is the carbon storage of aboveground herbaceous plants in the metal mine restoration area, C T-A It is the carbon storage of the aboveground parts of woody plants in the metal mine restoration area.

[0017] As a preferred embodiment of the present invention, the C H-A =DW1×CF1×44 / 12, wherein DW1 is the sum of the dry weights of the herbaceous plants in the sample plot; CF1 is the average carbon content of the aboveground parts of the herbaceous plants; and / or

[0018] The C T-A =W×CF2×44 / 12×0.001, where W is the sum of the aboveground biomass of woody plants in the sample plot, CF2 is the average carbon content of the aboveground part of woody plants in the sample plot, and W=a(D 2 H T ) b , where D is the diameter at breast height of woody plants, H T is the tree height of woody plants, a and b are regression coefficients.

[0019] As a preferred embodiment of the present invention, the C Below= C H-B +C T-B , where C H-B is the carbon storage of the underground part of herbaceous plants in the sample plot, C T-B is the carbon storage of the underground part of woody plants in the sample plot.

[0020] As a preferred embodiment of the present invention, the C H-B =DW2×CF3×44 / 12, where DW2 is the sum of the dry weights of the roots of the herbaceous plants in the sample plot, and CF3 is the average carbon content of the roots of the herbaceous plants in the sample plot; and / or

[0021] The C T-B The calculation method is C T-B =W×R1×CF2×44 / 12×0.001, where W is the aboveground biomass in the sample plot, R1 is the ratio of the underground biomass to the aboveground biomass in the sample plot, and CF2 is the average carbon content of the aboveground organisms in the sample plot.

[0022] As a preferred embodiment of the present invention, the C Litter =DW3×CF4×44 / 12, where DW3 is the dry weight of litter in the litter area within the sample plot, and CF4 is the average carbon content of litter in the sample plot.

[0023] As a preferred embodiment of the present invention, the C SOC =SOCD×S t×44 / 12, where SOCD is the soil carbon density of the soil sample, S t The area of ​​the metal mine restoration zone;

[0024] The SOCD=BD×SOC×H×0.1, wherein H is the soil thickness of the soil sample, SOC is the soil organic carbon content of the soil sample, and BD is the soil bulk density of the soil sample.

[0025] As a preferred embodiment of the present invention, the C SE =A×S t ×SOC T ×R C ×44 / 12×0.00001, where A is the average annual soil erosion per unit area in the metal mine restoration area, S t is the area of ​​the metal mine restoration area, SOC T is the soil organic carbon content of the surface soil sample, R C is the carbon emission coefficient caused by soil erosion, that is, the proportion of soil organic carbon released from soil erosion and converted into carbon dioxide in the atmosphere.

[0026] A=R2×K×L×S×C×P, where R2 is the rainfall erosion factor, K is the soil erodibility factor, L×S is the slope length and slope factor, C is the cover and management factor, and P is the soil and water conservation measures factor.

[0027] As a preferred embodiment of the present invention, the GHG E =GHG M +GHG el , among which GHG M CO2 emissions and GHG emissions from the production of materials required for acid mine drainage treatment el is the carbon dioxide emissions from electricity consumption during acid mine drainage treatment.

[0028] As a preferred embodiment of the present invention, the GHG M =Q m ×M material ×EF material , where Q m is the surface runoff in the metal mine restoration area, M material EF is the material consumption required to treat a unit volume of acid mine drainage. material is the carbon dioxide emission factor during the material production process.

[0029] As a preferred embodiment of the present invention, the GHG el =Q m ×E×EFBM, where Q mis the surface runoff in the metal mine restoration area, E is the electricity consumption required to treat unit volume of acid mine drainage, and EFBM is the baseline emission factor of the Chinese regional power grid.

[0030] As a preferred embodiment of the present invention, the Q m =C R ×Q×S t ×10, where C R is the surface runoff coefficient of the metal mine restoration area, Q is the total annual rainfall in the metal mine restoration area, S t The surface area of ​​the metal mine restoration area.

[0031] As a preferred embodiment of the present invention, the metering period is one quarter, one year or several years, and the specific period length can be adjusted according to actual needs.

[0032] As a preferred embodiment of the present invention, the ΔC T =ΔC E -ΔC SE -ΔGHG E , where ΔC E is the ecological carbon sink in the metal mine restoration area during the measurement period, ΔC SE ΔGHG is the change in carbon loss in the metal mine restoration area during the measurement period. E It is the change in carbon emissions in the metal mine restoration area during the measurement period.

[0033] As a preferred embodiment of the present invention, the ΔC E =C E,2 -C E,1 , where C E,1 is the carbon storage in the metal mine restoration area at the beginning of the measurement period, C E,2 The carbon stock in the metal mine restoration area at the end of the measurement period;

[0034] The ΔC SE =C SE,2 -C SE,1 , where C SE,1 is the carbon loss in the metal mine restoration area at the beginning of the measurement period, C SE,2 The amount of carbon lost in the metal mine restoration area at the end of the measurement period;

[0035] The ΔGHG E =GHG E,2 -GHG E,1 , among which GHG E,1 is the carbon emissions of the metal mine restoration area at the beginning of the measurement period, GHG E,2 It is the carbon emissions of the metal mine restoration area at the end of the measurement period.

[0036] The beneficial effects of the present invention are as follows: (1) Based on the detailed division of different ecological zones and the selection of sample plots within the metal mine restoration area, the present invention ensures the representativeness and comprehensiveness of data collection, and accurately calculates the carbon sink in the mine restoration area by accurately measuring the carbon content of the vegetation layer, soil and root system, and evaluating the carbon emissions from soil erosion and acid mine drainage treatment. The present invention uses a preset algorithm to standardize and calculate the collected data, which improves the efficiency of the calculation and the repeatability of the results, helps to improve and restore the damaged ecological environment, and can also contribute to the balance of the global carbon cycle by enhancing the carbon fixation capacity of soil and vegetation. This is of great strategic significance for achieving regional and even global carbon neutrality goals, and provides a reliable scientific basis for managers and decision makers of mine restoration projects. This method can not only reflect the true carbon sink status of the mine restoration area, but also provide important support for formulating effective carbon management strategies and evaluating the effects of ecological restoration, and has important practical application value. (2) The carbon sink calculation method of the present invention comprehensively considers the increase in carbon reserves, carbon loss caused by soil erosion, and carbon emissions during wastewater treatment. It not only accurately calculates the ecological carbon sink in the mine restoration area, but also provides a comprehensive and quantitative assessment of the total carbon sink capacity of the mine restoration area, which helps to more accurately understand the impact of restoration activities on the carbon cycle. DETAILED DESCRIPTION

[0037] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0038] In this application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0039] In this application, when referring to numerical ranges, unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges subsumed therein.

[0040] The present invention provides a method for calculating carbon sequestration in a metal mine restoration area, comprising the following steps:

[0041] (1) Based on the vegetation characteristics of the metal mine restoration area, the metal mine restoration area was divided into several different ecological region quadrats, and the sum of carbon storage in different ecological regions was calculated, which was recorded as C E ;

[0042] (2) Collect soil samples to evaluate the impact of soil erosion on carbon storage in the metal mine restoration area. By measuring the amount of soil erosion and the organic carbon content of the surface soil, calculate the amount of carbon loss caused by soil erosion, which is recorded as C SE ;

[0043] (3) Evaluate the impact of acid mine drainage treatment on carbon emissions in the remediation area. By obtaining the runoff conditions and relevant carbon emission factors in the remediation area, calculate the carbon emissions (GHG) generated by acid mine drainage treatment. E ;

[0044] (4) Set a measurement period and repeat steps (1) to (3) according to the measurement period, and compare the carbon storage C of the metal mine restoration area at the beginning and end of each measurement period. E,1 and C E,2 , carbon loss C SE,1 and C SE,2 , carbon emissions GHG E,1 and GHG E,2 , calculate the ecological carbon sink ΔC S , Carbon loss change ΔC SE and the change in carbon emissions ΔGHG E , calculate the total carbon sink ΔC in the metal mine restoration area during the measurement period according to the formula E , ΔC E =ΔC S -ΔC SE -ΔGHG E .

[0045] The present invention is based on the detailed division of different ecological zones and the selection of sample plots within the metal mine restoration area, which ensures the representativeness and comprehensiveness of data collection, and accurately calculates the carbon sink in the mine restoration area by accurately measuring the carbon content of the vegetation layer, soil and root system, as well as evaluating the carbon emissions from soil erosion and acid mine drainage treatment. The present invention uses a preset algorithm to standardize and calculate the collected data, which improves the efficiency of the calculation and the repeatability of the results, helps to improve and restore the damaged ecological environment, and can also contribute to the balance of the global carbon cycle by enhancing the carbon fixation capacity of soil and vegetation. This is of great strategic significance for achieving regional and even global carbon neutrality goals, and provides a reliable scientific basis for managers and decision makers of mine restoration projects. This method can not only reflect the true carbon sink status of the mine restoration area, but also provide important support for formulating effective carbon management strategies and evaluating the effects of ecological restoration, and has important practical application value.

[0046] The carbon sink calculation method of the present invention comprehensively considers the increase in carbon reserves, carbon loss caused by soil erosion, and carbon emissions during wastewater treatment. It not only accurately calculates the ecological carbon sink amount of the mine restoration area, but also provides a comprehensive and quantitative assessment of the total carbon sink capacity of the mine restoration area, which helps to more accurately understand the impact of restoration activities on the carbon cycle.

[0047] It should be noted that the carbon sink calculation method of the present invention first needs to determine the boundaries of the mine restoration area and the carbon sink measurement period, and collect relevant basic data, including information such as topography, vegetation type, soil type and historical mining activities.

[0048] In one embodiment, the ecological region sample includes at least one of a herbaceous region and a woody region.

[0049] More specifically, the present invention uses a ground survey method to divide the mine restoration area into multiple ecological zones, such as herbaceous and woody zones, based on restoration patterns. Appropriate sample plots are selected for each ecological zone and detailed surveys are conducted based on vegetation type, soil type, and topographical characteristics.

[0050] In one embodiment, the sample area of ​​the herbaceous area is 0.16~4m 2 The sample area of ​​the woody area is 25~400m 2 The number of sample plots in the herbaceous area and the woody area is ≥3. By clearly setting the sample plot area, the present invention ensures standardized measurement of carbon storage at different ecological levels, thereby improving the accuracy and repeatability of carbon sink assessment.

[0051] In one embodiment, the C E =C Above +C Below+C Litter +C SOC ;

[0052] Among them, the C Above is the carbon storage of aboveground organisms in the metal mine restoration area, where C Below is the carbon storage of underground organisms in the metal mine restoration area, the C Litter is the carbon storage of litter in the metal mine restoration area, the C SOC It is the soil organic carbon storage in the metal mine restoration area.

[0053] By subdividing the carbon reserves of different carbon pools, the present invention provides a multi-dimensional carbon sink assessment perspective, making the assessment results more detailed and providing a scientific basis for formulating effective carbon management strategies and ecological restoration measures.

[0054] In one embodiment, the C Above =C H-A +C T-A , wherein the C H-A is the carbon storage of aboveground herbaceous plants in the metal mine restoration area, C T-A It is the carbon storage of the aboveground parts of woody plants in the metal mine restoration area.

[0055] By distinguishing the carbon storage of the aboveground parts of herbaceous plants and woody plants, the present invention makes the assessment results more detailed and accurate, can more accurately assess the contribution of vegetation to carbon sequestration, and helps to optimize vegetation management and ecological restoration measures.

[0056] In one embodiment, the C H-A =DW1×CF1×44 / 12, where DW1 is the sum of the dry weights of the herbaceous plants in the sample plot; CF1 is the average carbon content of the aboveground parts of the herbaceous plants, where 44 is the molar mass of CO2 (the same below), and 12 is the molar mass of C (the same below); and / or

[0057] The C T-A =W×CF2×44 / 12×0.001, where W is the sum of the aboveground biomass of woody plants in the sample plot, CF2 is the average carbon content of woody plants in the sample plot, and W=a(D 2 H T ) b , where D is the diameter at breast height of woody plants, H T is the tree height of woody plants, a and b are regression coefficients obtained through statistical analysis based on field measured data, a is a coefficient related to tree density, and b is a coefficient related to the growth environment. The regression coefficient can also be selected by referring to the biomass equation proposed in existing studies.

[0058] The present invention calculates carbon reserves based on the dry weight and carbon content of herbaceous plants, which can easily and accurately evaluate the carbon reserves of the herbaceous layer, helping to quickly evaluate the carbon fixation capacity of herbaceous plants. The method for calculating the carbon content of the aboveground biomass of woody plants provides a standardized calculation process for carbon reserve assessment of woody plants, and estimates the aboveground biomass of woody plants by combining the diameter at breast height and tree height with a regression model, thereby improving the accuracy and efficiency of woody plant biomass estimation.

[0059] In one embodiment, the C Below= C H-B +C T-B , where C H-B is the carbon storage of the underground part of herbaceous plants in the sample plot, C T-B The underground carbon storage of woody plants in the sample plot was used to comprehensively evaluate the contribution of roots to the ecosystem carbon cycle by calculating the underground carbon storage of herbaceous and woody plants.

[0060] In one embodiment, the C H-B =DW2×CF3×44 / 12, where DW2 is the sum of the dry weights of the roots of the herbaceous plants in the sample plot, and CF3 is the average carbon content of the roots of the herbaceous plants in the sample plot; and / or

[0061] The C T-B The calculation method is C T-B =W×R1×CF2×44 / 12×0.001, where W is the aboveground biomass in the sample plot, R1 is the ratio of the underground biomass to the aboveground biomass in the sample plot, and CF2 is the average carbon content of the aboveground organisms in the sample plot.

[0062] The present invention calculates carbon storage by calculating the dry weight and carbon content of herbaceous plant roots and the ratio of underground to aboveground biomass of woody plants, which can fully reflect the contribution of plants to the carbon cycle and effectively improve the accuracy and efficiency of the calculation.

[0063] In one embodiment, the C Litter =DW3×CF4×44 / 12, where DW3 is the dry weight of litter in the litter area within the sample plot, and CF4 is the average carbon content of litter within the sample plot. By using the dry weight and carbon content of litter to calculate carbon storage, the assessment results can be more detailed and accurate, and the contribution of vegetation to carbon sequestration can be more accurately assessed, which is helpful to optimize vegetation management and ecological restoration measures.

[0064] In one embodiment, the C SOC =SOCD×S t ×44 / 12, where SOCD is the soil carbon density of the soil sample, S t The area of ​​the metal mine restoration zone;

[0065] Among them, soil carbon density refers to the content of organic carbon in soil per unit area.

[0066] The SOCD=BD×SOC×H×0.1, wherein H is the soil thickness of the soil sample, SOC is the soil organic carbon content of the soil sample, and BD is the soil bulk density of the soil sample. The present invention calculates soil carbon reserves based on soil carbon density and the area of ​​the remediation zone, providing an effective quantitative means for assessing soil carbon pools, making the assessment results more detailed and accurate.

[0067] In one embodiment, the C SE =A×S t ×SOC T ×R C ×44 / 12×0.00001, where A is the average annual soil erosion per unit area in the metal mine restoration area, S t is the area of ​​the metal mine restoration area, SOC T is the soil organic carbon content of the surface soil sample, R C The carbon emission coefficient caused by soil erosion is the proportion of carbon dioxide released from soil organic carbon due to soil erosion and converted into the atmosphere. It can be obtained through field monitoring of changes in soil carbon reserves, laboratory analysis of the organic carbon content in soil and sediment samples, and reference to existing research results or databases.

[0068] Definition of terms: A is the average annual soil erosion per unit area, which mainly refers to the average annual soil loss due to erosion in gullies or between gullies on slopes caused by rainfall and runoff.

[0069] The present invention calculates the amount of carbon loss caused by soil erosion through the amount of soil erosion and the organic carbon content of the surface soil, providing a scientific basis for evaluating the carbon loss caused by soil erosion.

[0070] A=R2×K×L×S×C×P, where R2 is the rainfall erosivity factor, which can be estimated through data such as rainfall amount, rainfall intensity and rainfall frequency; K is the soil erodibility factor, which can be determined by soil texture, organic matter content, structure and permeability; L×S is the slope length and slope factor, the slope length factor L is related to the length and slope of the slope, and the slope factor S is directly related to the inclination angle of the slope, both of which can be obtained through topographic maps or field measurements; C is the cover and management factor, which can be determined through information such as vegetation type, coverage, and tillage method; P is the soil and water conservation measure factor, which usually needs to be evaluated based on specific protection measures and implementation conditions.

[0071] Explanation of terms: R2 is the rainfall erosivity factor, which reflects the potential ability of rainfall to cause soil loss; K is the soil erodibility factor, which is an indicator of soil resistance to erosion and is used to reflect the sensitivity of soil to erosion; LS is the slope length and gradient factor (dimensionless), where L is the slope length factor, which is defined as a power function of the slope length, and S is the slope gradient factor; C is the cover and management factor (dimensionless), which refers to the ratio of soil loss under a specific crop or vegetation cover to the loss of continuous fallow land after cultivation under the same conditions of other factors; P is the soil and water conservation measure factor (dimensionless), which refers to the ratio of soil loss after soil and water conservation measures to soil loss due to downslope planting.

[0072] The present invention adopts the USLE model to estimate the amount of soil erosion. The parameters are easy to obtain and the calculation is simple. It can provide a relatively accurate estimation result, thereby ensuring the accuracy of the soil erosion data in the restoration area.

[0073] In one embodiment, the GHG E =GHG M +GHG el , among which GHG M CO2 emissions and GHG emissions from the production of materials required for acid mine drainage treatment el is the carbon dioxide emissions from electricity consumption during acid mine drainage treatment.

[0074] This paper provides a detailed calculation framework for evaluating the contribution of wastewater treatment to carbon emissions by distinguishing two different carbon emission sources.

[0075] In one embodiment, the GHG M =Q m ×M material ×EF material , where Q m is the surface runoff in the metal mine restoration area; M material The material consumption required to treat a unit volume of acid mine drainage needs to be determined according to the specific treatment technology. The required material quantity can be estimated through laboratory tests, small-scale trials or existing engineering data; EF material is the carbon dioxide emission factor in the material production process, which can be obtained through life cycle assessment (LCA) or by consulting relevant databases and literature.

[0076] The present invention calculates the carbon emissions caused by acid mine drainage treatment through surface runoff and emission factors of materials required for acid mine drainage treatment in the production process, providing a practical calculation method for evaluating the environmental impact of wastewater treatment.

[0077] In one embodiment, the GHG el=Q m ×E×EFBM, where Q m is the surface runoff in the metal mine restoration area; E is the electricity consumption required to treat a unit volume of acid mine drainage, which needs to be determined based on the actual treatment technology and equipment used, and can be obtained through energy consumption tests or data provided by equipment manufacturers; EFBM is the baseline emission factor of the Chinese regional power grid, which can be obtained through national or local energy statistics, information provided by power grid operators or environmental impact assessment reports.

[0078] Definition of term: The grid baseline emission factor refers to the average carbon dioxide emissions per unit of electricity produced during the electricity production process.

[0079] This method calculates the carbon emissions of electricity consumption by combining surface runoff and grid baseline emission factors, providing a standardized calculation method for assessing the contribution of energy use to carbon emissions.

[0080] In one embodiment, the Q m =C R ×Q×S t ×10, where C R is the surface runoff coefficient of the metal mine restoration area, Q is the total annual rainfall in the metal mine restoration area, S t The surface area of ​​the metal mine restoration area.

[0081] Glossary: ​​The surface runoff coefficient is the ratio of rainfall to surface runoff. This method calculates surface runoff volume using the surface runoff coefficient and annual rainfall, providing a fundamental hydrological parameter estimation tool for carbon cycle research.

[0082] In one embodiment, the metering period is one quarter, one year or several years, and the specific period length can be adjusted according to actual needs.

[0083] In one embodiment, the ΔC T =ΔC E -ΔC SE -ΔGHG E , where ΔC E is the ecological carbon sink in the metal mine restoration area during the measurement period, ΔC SE ΔGHG is the change in carbon loss in the metal mine restoration area during the measurement period. E It is the change in carbon emissions in the metal mine restoration area during the measurement period.

[0084] This method comprehensively reflects the net carbon sink capacity of the metal mine restoration area within a certain period by setting a measurement period and repeatedly executing the carbon sink calculation steps, realizing the dynamic evaluation and quantification of the carbon sink capacity of the metal mine restoration area, which helps to more accurately evaluate the carbon sink potential of the metal mine restoration area.

[0085] In one embodiment, the ΔC E =C E,2 -C E,1 , where C E,1 is the carbon storage in the metal mine restoration area at the beginning of the measurement period, C E,2 The carbon stock in the metal mine restoration area at the end of the measurement period;

[0086] The ΔC SE =C SE,2 -C SE,1 , where C SE,1 is the carbon loss in the metal mine restoration area at the beginning of the measurement period, C SE,2 The amount of carbon lost in the metal mine restoration area at the end of the measurement period;

[0087] The ΔGHG E =GHG E,2 -GHG E,1 , among which GHG E,1 is the carbon emissions of the metal mine restoration area at the beginning of the measurement period, GHG E,2 It is the carbon emissions of the metal mine restoration area at the end of the measurement period.

[0088] It should be noted that the units of carbon storage, carbon loss, carbon emission and carbon sink mentioned in the present invention are tCO2; the unit of plant dry weight is t; the unit of biomass is kg; the unit of diameter at breast height is cm; the unit of tree height is m; the unit of soil carbon density is tC / ha; the unit of area is ha; the unit of soil thickness is cm; the unit of soil organic carbon content is g / kg; the unit of soil bulk density is g / cm 3 ; The unit of annual soil erosion per unit area is t / km 2 ·yr; surface runoff unit is m 3 ; Material consumption unit is t / m 3 The unit of carbon dioxide emission factor in the material production process is tCO2 / t; the unit of electricity consumption is MWh / m 3 The unit of China's regional power grid baseline emission factor is tCO2 / MWh; the unit of monthly rainfall and annual rainfall is mm; the unit conversion factor can be adjusted according to the actual units used for each parameter.

[0089] The following examples are provided to facilitate understanding of the present invention. These examples are not provided to limit the scope of the claims.

[0090] Example 1

[0091] A method for calculating the ecological carbon sinks, carbon losses, and carbon emissions of a metal mine restoration area (a polymetallic mine restoration area) at the beginning of a measurement period (in this example, the measurement period is 5 years), comprising the following steps:

[0092] (1) Through ground survey, it was found that there was no obvious vegetation in the abandoned metal mine site, and the carbon storage of aboveground organisms, underground organisms and litter was zero; 2 The sum of carbon storage in different ecological zones of a polymetallic mine restoration area is denoted as C E,1 ;

[0093] Soil samples were obtained at different depths using the ring knife method, and the soil organic carbon content was analyzed. The soil carbon density was calculated based on the soil thickness and soil bulk density.

[0094] Among them, C E,1 =C Above,1 +C Below,1 +C Litter,1 +C SOC,1 =0+0+0+49.7046=49.7046t CO2

[0095] C Above,1 =C H-A +C T-A =0t CO2

[0096] C H-A,1 =DW1×CF1×44 / 12=0t CO2

[0097] C T-A,1 =W×CF2×44 / 12×0.001=0t CO2, W=a(D 2 H T ) b =0kg

[0098] C Below,1= C H-B +C T-B =0t CO2

[0099] C H-B,1 =DW2×CF3×44 / 12=0t CO2

[0100] C T-B,1 =W×R1×CF2×44 / 12×0.001=0t CO2

[0101] C Litter,1=DW3×CF4×44 / 12=0t CO2

[0102] C SOC,1 =SOCD×S t ×44 / 12=13.5558×1×44 / 12=49.7046t CO2

[0103] SOCD=BD×SOC×H×0.1=1.111×6.1007×20×0.1=13.5558 t C / ha

[0104] (2) Apply the USLE model, combine the actual rainfall data, terrain factors and vegetation coverage of the metal mining area, select a suitable calculation method (the same calculation method is used in Example 2 and Example 3), estimate the annual average soil erosion per unit area, calculate the organic carbon content released by soil erosion in the soil organic carbon pool of the metal mining area and the ratio of its conversion to carbon dioxide in the atmosphere, and calculate the carbon loss caused by soil erosion based on the organic carbon content of the surface soil. Calculate the carbon loss caused by soil erosion and record it as C SE,1 ;

[0105] According to the metal mining area

[0106] C SE,1 =A×S t ×SOC T ×R C ×44 / 12×0.00001=775.0508×1×6.1007×0.04318×44 / 12×0. 00001=0.007486t CO2

[0107] A=R2×K×L×S×C×P=460.5649×0.1761×2.1257×9.99×0.5×0.9=775.0508t / km 2 ·yr.

[0108] R2=∑1.735×10^[1.5×lg(Pi 2 / P)-0.8188]=460.5649

[0109] Where Pi is the monthly precipitation (mm); P is the total annual precipitation (mm).

[0110] K={0.2+0.3×exp[-0.256×Sa×(1-Si / 100)]}×[Si / (Cl+Si)]^0.3×{1-0.25×C F / [C F +exp(3.72-2.95×C F)]}×{1-0.7×Sn / [Sn+exp(-5.51+22.9×Sn)]}=0.1761

[0111] Where: Sa, Si, Cl, C F represent sand, silt, clay and organic carbon content (%), Sn=1-Sa / 100;

[0112] S=21.9×sin30°-0.96= 9.99

[0113] L=(λ / 22.13)^0.5=(100 / 22.13)^0.5=2.1257

[0114] C=Min(C NA )+Range(C NA )×(1-F cover )=0.01

[0115] Where C NA is the range of C factor values ​​for each land use type, F cover Normalized between 0 and 1, it describes the percentage of land covered by vegetation.

[0116] The soil and water conservation measures factor P reflects the reduction in soil loss after taking soil and water conservation measures, and is taken as 0.9 based on the soil and water conservation situation of the mine.

[0117] (3) The metal mining area uses lime neutralization to treat acid mine drainage. Therefore, by measuring the surface runoff of the mining area before restoration, the lime consumption and electricity consumption required for treating acid mine drainage are estimated based on the relevant parameters provided by the acid mine drainage treatment agency. The carbon dioxide emission factor in the lime production process is queried in conjunction with relevant literature. Based on the China Regional Grid Baseline Emission Factor provided in the "2019 Emission Reduction Project China Regional Grid Baseline Emission Factor", the carbon emissions in the wastewater treatment process are calculated. The impact of acid mine drainage treatment on carbon emissions in the restoration area is evaluated. By obtaining the runoff conditions and relevant carbon emission factors in the restoration area, the carbon emissions (GHG) generated by acid mine drainage treatment are calculated. E,1 ;

[0118] GHG E,1 =GHG M,1 +GHG el,1 =107.7211t CO2

[0119] GHG M,1 =Q m ×M material ×EF material=12183.1563×0.0075×0.75=68.5303t CO2

[0120] GHG el,1 =Q m ×E×EFBM=12183.1563×0.004×0.8042=39.1908t CO2

[0121] Q m =C R ×Q×S t ×10=12183.1563 m 3

[0122] Example 2

[0123] A method for calculating ecological carbon sinks, carbon losses, and carbon emissions in a metal mine restoration area (a polymetallic mine restoration area, the same as in Example 1) at the end of a measurement period comprises the following steps:

[0124] (1) Through ground survey, according to the vegetation characteristics of the metal mine restoration area, 10,000 m 2 A polymetallic mine restoration area was divided into two ecological zones: herbaceous and woody. The sum of carbon storage in different ecological zones was calculated and recorded as C E,2 ;

[0125] Soil samples were obtained at different depths using the ring knife method, and the soil organic carbon content was analyzed. The soil carbon density was calculated based on the soil thickness and soil bulk density.

[0126] In both herbaceous and woody areas, we recorded plot area, vegetation type, and tree species composition. We also collected herbaceous, litter, and root samples and measured their dry weight and carbon content. We also measured the diameter at breast height and tree height of the tree layer and estimated the aboveground biomass of the trees, using the relevant parameters of the biomass equation in the "Carbon Storage in China's Forest Ecosystems—Biomass Equation."

[0127] Among them, the sample area of ​​the herbaceous area is 1m 2 (1m*1m), the sample area of ​​the woody area is 100m 2 (10m*10m), the number of sample plots in the herbaceous area and the woody area are both 10.

[0128] in,

[0129] C E,2 =C Above,2 +C Below,2 +C Litter,2 +C SOC,2 =12.2988+4.2371+8.5014+89.6471=114.6844tCO2

[0130] C Above,2 =C H-A +C T-A =1.3971+10.9017=12.2988t CO2

[0131] C H-A,2 =DW1×CF1×44 / 12=1.6912×0.2253×44 / 12=1.3971t CO2

[0132] C T-A,2 =W×CF2×44 / 12×0.001=6180×0.4811×44 / 12×0.001=10.9017t CO2

[0133] W=∑W i =∑a(D i 2 H T ) b =6180kg

[0134] C Below,2= C H-B +C T-B =0.1271+4.1100=4.2371t CO2

[0135] C H-B,2 =DW2×CF3×44 / 12=0.1924×0.1808×44 / 12=0.1271t CO2

[0136] C T-B,2 =W×R1×CF2×44 / 12×0.001=6180×0.377×0.4811×44 / 12×0.001=4.1100t CO2

[0137] C Litter,2 =DW3×CF4×44 / 12=10.0240×0.2313×44 / 12=8.5014t CO2

[0138] C SOC,2 =SOCD×S t ×44 / 12=24.4492×1×44 / 12=89.6471t CO2

[0139] SOCD=BD×SOC×H×0.1=1.1169×10.9451×20×0.1=24.4492t C / ha

[0140] (2) Applying the USLE model, combined with rainfall data, topographic factors, and vegetation coverage, the annual average soil erosion per unit area was estimated. The organic carbon content released by soil erosion in the soil organic carbon pool of the metal mining area and the ratio of its conversion to atmospheric carbon dioxide were calculated. The carbon loss caused by soil erosion was calculated based on the organic carbon content of the surface soil. The carbon loss caused by soil erosion was calculated and recorded as C SE,2 ;

[0141] C SE,2 =A×S t ×SOC T ×R C ×44 / 12×0.00001×5=14.8651×1×10.9451×0.04318×44 / 12×0.00001×5=0.000258t CO2

[0142] A=R2×K×L×S×C×P=479.7462×0.1736×2.1257×9.3296×0.01×0.9=14.8651t / km 2 ·yr

[0143] (3) As the implementation of the remediation measures has enabled the surface water quality to meet the corresponding environmental standards, there is no need for acid wastewater treatment, thus avoiding the associated carbon emissions and achieving zero carbon emissions caused by acid wastewater treatment.

[0144] GHG E,2 =GHG M,2 +GHG el,2 =0t CO2

[0145] (4) By comparing the carbon storage C in the metal mine restoration area at the beginning and end of each measurement period E,1 and C E,2 , carbon loss C SE,1 and C SE,2 , carbon emissions GHG E,1 and GHG E,2 , calculate the ecological carbon sink ΔC E , Carbon loss change ΔC SE and the change in carbon emissions ΔGHG E .

[0146] ΔC E =C E,2 -C E,1 =114.6844-49.7046=64.9798t CO2

[0147] ΔC SE =C SE,2 -C SE,1=0.000258-0.007486=-0.007228t CO2

[0148] ΔGHG E =GHG E,2 -GHG E,1 =0-107.7211=-107.7211t CO2

[0149] (5) Evaluate the carbon sink capacity of the metal mine after restoration, and calculate the total carbon sink ΔC of the metal mine restoration area during the measurement period according to the formula T ;

[0150] ΔC T =ΔC E -ΔC SE -ΔGHG E =64.9798-(-0.007228)-(-107.7211)=172.7081t CO2;

[0151] It can be seen from Examples 1 and 2 that, after statistical analysis, after five years of restoration of the polymetallic mining area, the ecological carbon sink in the restoration area increased from 49.7046t CO2 to 114.6844t CO2, the cumulative carbon loss decreased from 0.007486t CO2 to 0.000258t CO2, the cumulative carbon emissions decreased from 107.7211t CO2 to 0, and the total carbon sink reached 172.7046t CO2.

[0152] Results Analysis and Reporting: An assessment of the mine's carbon sequestration capacity before and after restoration five years revealed that ecological restoration measures significantly increased the region's total carbon sequestration capacity. By implementing effective revegetation and soil management strategies, the mine successfully enhanced the ecosystem's carbon sequestration capacity while reducing carbon losses due to soil erosion. Furthermore, the excellent restoration results have essentially eliminated the need for acid drainage treatment, effectively avoiding associated carbon emissions.

[0153] Example 3

[0154] A method for calculating ecological carbon sinks in a metal mine restoration area (a pyrite restoration area) after restoration, comprising the following steps:

[0155] (1) Through ground survey, since the ecological restoration strategy adopted in the restoration area focuses on the reconstruction of herbaceous vegetation, there is no need to measure the woody area. According to the vegetation characteristics of the metal mine restoration area, at 33578.5m 2 In a pyrite mine restoration area, 10 samples with an area of ​​1m 2 (1m*1m) herbaceous area, calculate the sum of carbon storage in different ecological regions, denoted as CE ;

[0156] Soil samples were collected at different depths using the ring knife method to analyze soil organic carbon content. The soil carbon density was calculated based on soil thickness and soil bulk density.

[0157] In this step, the area of ​​the selected plots will be accurately measured, and detailed information such as vegetation type will be recorded. Subsequently, soil and herbaceous plant samples will be collected, and the dry weight and carbon content of the herbaceous plant samples will be measured to accurately estimate their carbon storage.

[0158] Among them, the sample area of ​​the herbaceous area is 1m 2 (1m*1m), the sample area of ​​the woody area is 100m 2 (10m*10m), the number of sample plots in the herbaceous area and the woody area are both 10.

[0159] in,

[0160] C E =C Above +C Below +C SOC ==30.6895+2.7689+403.6306=437.0890t CO2

[0161] C Above =C H-A =30.6895t CO2

[0162] C H-A =DW1×CF1×44 / 12=37.2490×0.2247×44 / 12=30.6895t CO2

[0163] C Below= C H-B =2.7689t CO2

[0164] C H-B =DW2×CF3×44 / 12=4.2353×0.1783×44 / 12=2.7689t CO2

[0165] C SOC =SOCD×S t ×44 / 12=32.7832×3.35785×44 / 12=403.6306t CO2

[0166] SOCD=BD×SOC×H×0.1=0.86×19.06×20×0.1=32.7832t C / ha

[0167] The analysis shows that the ecological restoration strategy of the pyrite mining area has achieved remarkable results in improving carbon sequestration capacity. It not only confirms the important role of herbaceous vegetation reconstruction in carbon sequestration, but also highlights the potential of soil as a long-term carbon storage medium. It further emphasizes the importance of reasonable soil management and vegetation restoration measures for improving the carbon sequestration capacity of metal mining areas, and provides a scientific basis for future ecological restoration and carbon management.

[0168] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method for calculating carbon sinks in a metal mine restoration area, characterized in that: The following steps are involved: (1) Based on the vegetation characteristics of the metal mine restoration area, the metal mine restoration area was divided into several different ecological region quadrats, and the sum of carbon storage in different ecological regions was calculated, which was recorded as C E ; (2) Collect soil samples to evaluate the impact of soil erosion on carbon storage in the metal mine restoration area. By measuring the amount of soil erosion and the organic carbon content of the surface soil, calculate the amount of carbon loss caused by soil erosion, which is recorded as C SE ; (3) Evaluate the impact of acid mine drainage treatment on carbon emissions in the remediation area. By obtaining the runoff conditions and relevant carbon emission factors in the remediation area, calculate the carbon emissions (GHG) generated by acid mine drainage treatment. E ; (4) Set a measurement period and repeat steps (1) to (3) according to the measurement period, and compare the carbon storage C of the metal mine restoration area at the beginning and end of each measurement period. E,1 and C E,2 , carbon loss C SE,1 and C SE,2 , carbon emissions GHG E,1 and GHG E,2 , calculate the ecological carbon sink ΔC E , Carbon loss change ΔC SE and the change in carbon emissions ΔGHG E , calculate the total carbon sink ΔC in the metal mine restoration area during the measurement period according to the formula T , ΔC T =ΔC E -ΔC SE -ΔGHG E ; The C E =C Above +C Below +C Litter +C SOC ; wherein, the C Above is the carbon storage of aboveground organisms in the metal mine restoration area, where C Below is the carbon storage of underground organisms in the metal mine restoration area, the C Litter is the carbon storage of litter in the metal mine restoration area, the C SOC Soil organic carbon storage in metal mine restoration areas; The C SE =A×S t ×SOC T ×R C ×44 / 12×0.00001, where A is the average annual soil erosion per unit area in the metal mine restoration area, S t is the area of ​​the metal mine restoration area, SOC T is the soil organic carbon content of the surface soil sample, R C is the carbon emission coefficient caused by soil erosion; A=R2×K×L×S×C×P, where R2 is the rainfall erosivity factor, K is the soil erodibility factor, L×S is the slope length and slope factor, C is the cover and management factor, and P is the soil and water conservation measures factor; The GHG E =GHG M +GHG el , among which GHG M CO2 emissions and GHG emissions from the production of materials required for acid mine drainage treatment el is the carbon dioxide emissions from electricity consumption during acid mine drainage treatment.

2. The carbon sink calculation method for metal mine restoration areas according to claim 1 is characterized in that: The ecological region sample plot includes at least one of a herbaceous region and a woody region.

3. The carbon sink calculation method for a metal mine restoration area according to claim 2, characterized in that: The sample area of ​​the herbaceous area is 0.16~4m 2 The sample area of ​​the woody area is 25~400m 2 The number of sample plots in the herbaceous area and woody area is ≥3.

4. The carbon sink calculation method for a metal mine restoration area according to claim 1, characterized in that: The C Above =C H-A +C T-A , wherein the C H-A is the carbon storage of aboveground herbaceous plants in the metal mine restoration area, C T-A It is the carbon storage of the aboveground parts of woody plants in the metal mine restoration area.

5. The carbon sink calculation method for metal mine restoration areas according to claim 4 is characterized in that: The C H-A =DW1×CF1×44 / 12, wherein DW1 is the sum of the dry weights of the herbaceous plants in the sample plot; CF1 is the average carbon content of the aboveground parts of the herbaceous plants; and / or The C T-A =W×CF2×44 / 12×0.001, where W is the sum of the aboveground biomass of woody plants in the sample plot, CF2 is the average carbon content of the aboveground part of woody plants in the sample plot, and W=a(D 2 H T ) b , where D is the diameter at breast height of woody plants, H T is the tree height of woody plants, a and b are regression coefficients.

6. The carbon sink calculation method for metal mine restoration areas according to claim 1 is characterized in that: The C Below= C H-B +C T-B , where C H-B is the carbon storage of the underground part of herbaceous plants in the quadrat, C T-B is the carbon storage of the underground part of woody plants in the sample plot.

7. The carbon sink calculation method for a metal mine restoration area according to claim 6, characterized in that: The C H-B =DW2×CF3×44 / 12, where DW2 is the sum of the dry weights of the roots of the herbaceous plants in the sample plot, and CF3 is the average carbon content of the roots of the herbaceous plants in the sample plot; and / or The C T-B The calculation method is C T-B =W×R1×CF2×44 / 12×0.001, where W is the aboveground biomass in the sample plot, R1 is the ratio of the underground biomass to the aboveground biomass in the sample plot, and CF2 is the average carbon content of the aboveground organisms in the sample plot.

8. The carbon sink calculation method for metal mine restoration areas according to claim 1 is characterized in that: The C Litter =DW3×CF4×44 / 12, where DW3 is the dry weight of litter in the litter area within the sample plot, and CF4 is the average carbon content of litter in the sample plot.

9. The carbon sink calculation method for a metal mine restoration area according to claim 1, characterized in that: The C SOC =SOCD×S t ×44 / 12, where SOCD is the soil carbon density of the soil sample, S t The area of ​​the metal mine restoration zone; The SOCD=BD×SOC×H×0.1, wherein H is the soil thickness of the soil sample, SOC is the soil organic carbon content of the soil sample, and BD is the soil bulk density of the soil sample.

10. The carbon sink calculation method for metal mine restoration areas according to claim 1, characterized in that: The GHG M =Q m ×M material ×EF material , where Q m is the surface runoff in the metal mine restoration area, M material EF is the material consumption required to treat a unit volume of acid mine drainage. material CO2 emission factors for the production of the material; and / or The GHG el =Q m ×E×EFBM, where Q m is the surface runoff in the metal mine restoration area, E is the electricity consumption required to treat unit volume of acid mine drainage, and EFBM is the grid baseline emission factor.

11. The carbon sink calculation method for a metal mine restoration area according to claim 10, characterized in that: The Q m =C R ×Q×S t ×10, where C R is the surface runoff coefficient of the metal mine restoration area, Q is the total annual rainfall in the metal mine restoration area, S t The surface area of ​​the metal mine restoration area.

12. The carbon sink calculation method for a metal mine restoration area according to claim 1, characterized in that: The ΔC T =ΔC E -ΔC SE -ΔGHG E , where ΔC E is the ecological carbon sink in the metal mine restoration area during the measurement period, ΔC SE ΔGHG is the change in carbon loss in the metal mine restoration area during the measurement period. E It is the change in carbon emissions in the metal mine restoration area during the measurement period.

13. The carbon sink calculation method for a metal mine restoration area according to claim 12, wherein the ΔC E =C E,2 -C E,1 ,in, C E,1 is the carbon storage in the metal mine restoration area at the beginning of the measurement period, C E,2 The carbon stock in the metal mine restoration area at the end of the measurement period; The ΔC SE =C SE,2 -C SE,1 , where C SE,1 is the carbon loss in the metal mine restoration area at the beginning of the measurement period, C SE,2 The amount of carbon lost in the metal mine restoration area at the end of the measurement period; The ΔGHG E =GHG E,2 -GHG E,1 , among which GHG E,1 is the carbon emissions of the metal mine restoration area at the beginning of the measurement period, GHG E,2 It is the carbon emissions of the metal mine restoration area at the end of the measurement period.